Machine gun



E. LUDORF m., m; w23.

MACHINE GUN Filed May 13, 1921 atvented Feb. 20, 1923..

UNITED STATES ERNST LUDORF, O BERNE, SWITZERLAND.

MACHINE GUN.

' Application led May 13,

Z'o all whomz't may concern.'

Be it known that I, ERNST LUDORF, a citizen of the German Re ublic, Yresiding at Berne, Engerstrasse o. 6a, Switzerland, have invented new and useful Improvements in Machine Guns, of whlch the following is a description.

The present invention relates to an automatic machine gun.

One object of the invention., is to prov'ide a machine gun of very greatly simplified construction in which the number of Working parts is very small, the gun being thoroughly eicient in operation and of very light weight.

A further object of the invention consists in the provision of means to damp the recoil in such a manner that the initial speed olf the projectiles leaving the muzzle of the gun is the same in vertical or hori zontal position of the gun.

Another object of the invention consists in providing a Huid brake of an improved construction which is of light weight and very compact.

y A further object of the invention consists in the provision of means to feed the projectiles positively into the gun.

With these and y other objects in View the invention resides in the parts and combination of parts hereinafter described and particularly set forth. in the claims appended hereto.

In thedrawings which form a part of this specification:

Fig. 1 is a partial sectional elevation of an automatic machine gun, the breech casing being closed.'

F ig. 2 is a partialV sectional elevation of the gun showing a section on line Gr--H of Fig. 1, the breech case being open.

Fig. 3 is a section on line A-B of Fig. 1 showing the breech casing with the Huid brake. l

Fig. 4 is a section on line C-D of Fig.

1 showing the fluid brake.

1921. Serial N0. 469,275.

screw 40. In the casing 2 the breech bolt 5 is slidably mounted which carries atV its f ront end the extractor 6 for theextractlon of the empty cartridge cases 7. In the bore of the breech bolt 5 the firing pin 8 is slidably mounted which is pressed forward by a spring 9 lodged in the said bore. The rear end of the breech bolt 5 forms a piston 17 fitting the cylinder 4. On the piston 17 a plate 42 is fastened which is slidabl 41 and a wall o the cylinder 4. A. spring 25 arranged within the cylinder 4 tends to throw the breech bolt forward into the position shown in Fig. 1. The piston 17 guided between a plate is provided with a cross-slot 24 in which a l slide 23 is arranged. A spring arranged within said cross slot presses the slide 23 against a slanting wall 22 of the casing 4, the cross area of the cylinder being somewhat less at the rear end. The cylinder 4 is filled with a suitable Huid, for instance ton 17. @ver the bore 20 a plate 21 is placed which is fixed to a rod 30. The rod 30 is slidably mounted in the casing 4; a spring 13 acting on said rod 30 tends to close the said boreA 20. To the front end 29 of the rod 30 a slide 12 is linked. The slide 12 is movably arranged in a guide 27; it slides over a plate 10 and is guided by ribs 28. The' plate 1() is hinged at 11 andA serves as a stop for the slide 12. The guide 27 is rotatably mounted on the pivotal bolt 11 of the breech casing; `it is moreover provided with cam faces 26 projecting into the path of a lug 14`orming part of the breech bolt 5. The slide 12 is provided with a nose 16 serving as a stop for a lug 15 of the firing pin 8. 0n the guide 27 a double armed lever 31 is journalle'd one arm of which projects in the path of the lug 14 of the breech bolt 5^ the other arm abutting on the plate 10 in such a manner that the plate 10 is pressed down against the action of a spring 45 if the breech bolt is thrown into firing position, whereby the plate 10 frees the slide 12. rllhe spring 13 throws the rod 30 with the slide 12 forward; the

firing pini8' being released is thrown forward by the spring 9 and fires the cartridge 7 which has been inserted in the chamber ber 19 andfrom the chamber 19 through the'bore -20 into the cylinder 4. By the rearward movement of the piston 17 the spring 25 is-compressed, the slide 12 which rests on the-lug 14 is brought back to its initial position, until it falls behind the.

stop plate 10. -The spring 13 is compressed and vslide 21 frees the` bore20, allowing the fluid to flow freely into the cylinder 4. The lug 14 of the breech b'olt passes over the cam faces 26 of the guide 27 which swings aboutv bolt 1l.y After the lug 14 has passed over the guide 27 the spring 45 presses the plate 10 against the slide 12 locking the same. As soon as the projec' tile has left the barrel the spring 25 pushes the breech bolt 5 forward. A new cartridge is inserted into the chamber. The lug 14 asses over the cam faces 26 of the guide 2 and strikes against lever 31, the

Aplate 10 releases the slide 12 and the rod 30, which are thrown forward freeing the firing pin which fires the cartridge. Thel spring 25 has not to stand a very great strain as the effect .of the recoil is trans` ferred mainly to the iluid.

The device to feed the cartridge comprises a slide 32 having an arm 33 slidably mounted in the breech casing and project' ing with its free end into the path of the lug 14. If the breech bolt 5 moves rearwardly the slide 32 takes part in thismovement.v The slide32 is provided with cams 34 adapted to swing a double armed lever 35, 36 about its pivot. "The arm 36 pushes cartridges 7 which are fed by al channel 37 into the slot 38 one by one into said barrel chamber in front of the breech bolt 5.

The empty' cartridge case is thrown out throughthe slot 38. The slide 32 is brought back toits initial position by a spring suitabl arranged.

'IYo insert the first cartridge the nut-40 is 1,44e,ase

unscrewed, the cylinder v4 with the breech bolt 5 is withdrawn and the one cartridge inserted through the channel 37.

The slide 21v frees the bore 2O only after the cartridge has been fired, thus the fluid has to withstand the gas pressure.'

I wish to point out that various changes may be made without departing from the spirit of my invention. 'i

What I claim and wish to secure by Letters Patent is I Y 1. A machine gun of the kind hereinbefore referred to having a barrel, a breech casing, a breech bolt slidably arranged in said breech casing, a cylinder co-axial ;to said breech bolt, a piston on said breech bolt slidable inv said cylinder, a fluid within said cylinder, said cylinder having openings beyond the limits of the movement of the piston, a slide governing one of said openings and operating means for said slide, said operating means actuated by the breech bolt to open 'and close said opening.

2. A machine gun of the kind hereinbefore referred to having a barrel, -a breech casing, a breech bolt slidably arranged in said breech casing, a cylinder coaxial to said breech bolt, a piston on said breech bolt slidable in said cylinder,'a fluid within said cylinder, said cylinder having openings beyond the limits lof movement of the-piston, said cylinder and piston having rectangular cross-section, the cross-section decreasing gradually, a slide in said piston, and a spring acting on said slide to progressively piston.

3. A machine gun of the kind hereinbefore referred to having a barrel, a breech casing, a breech bolt slidably arranged in sard breech casing, a cylinder co-axial to said breech bolt, a piston on said breech bolt slidable in said cylinder, a fluid within said cylinder, said cylinder having openings bebrake the rearward movement of theV yond the limits of movement of the piston, 4

a slide governing one of said openings, a lug on the breech bolt co-acting with said slide, and means for automatically discon-v necting said slide from the breech bolt.

In witness whereof I aiiix my signature.

ERNST LUDORF. 

